Doubles throwout for sheet feeding mechanism



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A. R. WEIBEL. ET AL 2 DOUBLES THROWOUT FOR SHEET FEEDING MECHANISM X 2Sheets-Sheet 1 Filed Jan. 25, 1935 lNVENTORS 'IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII/ A. R. WEIBEL ET AL.

DOUBLES THROWOUT FOR SHEET FEEDING MECHANISM Filed Jam 25; 1955 gSheets-Sheet 2 Patented Mar. 1, 1938 r orrice DOUBLES THROWOUT FOR.SHEET FEEDING NIEC'HANISM Pennsylvania Application January 25, 1935,Serial No. 3,461

1 Claim.

This invention relates to the feeding of sheets through an apparatuswhere the sheets are to be processed; and is for a throwout mechanismfor detecting two sheets which adhere together and throwing of both orone of them out of the regular line of feed, whereby they will gothrough the processing until they have been manually separated andplaced back in the feeding mechanlsm.

The invention has particular application to the feeding of sheet ironthrough tinning pots in the manufacture of tin plate, and the inventionwill be described in this connection, although it will be understoodthat theinvention-is applicable to various uses where sheets are to befed singly through processing equipment by automatic feeders.

In the making of tin plate the iron sheets are placed in packs in afeeding apparatus. This feeding apparatus is so constructed as tonormally remove one sheet at a time from the pack and deliver it tofeeding rolls. It frequently happens, however, that two sheets willadhere and will be handled by the feeding mechanism as a single sheet.Obviously, two sheets so adhering could not be properly tinned.

Automatic throwouts have heretofore been provided for the purpose ofdetecting sheets which so adhere and for throwing them out of the normalline of travel, but as heretofore constructed these devices haveoperated on the variation of thickness of the two sheets over thethickness of. the single sheet. The sheets are relatively, thin. Anyapparatus which responds to the variation in thickness of two sheetsover one sheet must necessarily be quite delicate and have a very niceadjustment. Because of the delicate construction of such devices, andbecause of the nice adjustment in which they have to be kept in order tofunction properly, they have not been altogether satisfactory and theyrequire frequent attention.

According to the present invention. a doubles throwout is provided whichresponds to changes in flexibility or resiliency of the metal ratherthan to variations in thickness. The leading edge of a single sheet ofmetal is more resilient and more easily flexed than are the leadingedges of two sheets which are sticking together. The present inventionutilizes this difference in flexibility or resiliency. The result isthat the apparatus may be more ruggedly constructed, will not have to beso closely adjusted and will not need as frequent attention and willfunction with a greater degree of satisfaction and accuracy.

The invention may be readily understood by reference to the accompanyingdrawings, in which In the drawings, 2 designates a tank adapted to bepositioned at the front of a tin pot. Within the tank 2 is a verticaladjustable basket 3 adapted to receive and support in an inclinedposition a series or pack of sheets to be processed, this pack of sheetsbeing designated 4. The

tank v2 is kept full of water so that the sheets 4 L are at all timessubmerged while they are resting in the basket.

Supported over the top of the tank 2 isa shaft 5 which is periodicallyoscillated. The shaft 5 carries one or more supporting members 6 havingrollers l thereon. The supporting member 6 and the rollers 1 provide aguideway for a slidable arm 8. This arm 8 carries a head 9 on which areone or more suction cups Ill. As.

shown in Figure 2, the arm 8 and the head 9 have'passageways l l thereincommunicating with the interior of the cup or cups Ill. The passagewayIt is connected through a flexible tubing H! with a suction pump whichis periodically operated to create and hold a suction in the cup H] 5and which relieves the suction at a predetermined time. The constructionand arrangement of one form of pump mechanism is more fully shown andclaimed in our copending application above referred to, and in whichapplication a sheet feeding device is also claimed.

When the shaft 5 is rocked in a clockwise direction through a limitedarc, the support 5 is tilted forwardly and the arm 8 slides down untilthe suction cup or cups lll contact the outer sheet in the stack 4. Atthis time, a suction is generated in the cup I0, and the shaft 5 startsto move through a limited arc in a counterclockwise direction. Thisaction serves to draw the upper edge of the sheet which is engaged bythe suction cup through the path indicated in dotted lines, the edge ofthe sheet starting to travel on a radius, but as the arm 8 begins to betipped rearwardly instead of forwardly, it begins to slide back, pullingthe leading edge of the sheet down, the edge of the sheet thusdescribing a curve which is more of a parabola than a true arc.

It will be seen that by reason of this arrangement the sheets are bentrelatively sharply as they are lifted and turned from the inclinedpositions they occupy in the basket to the substantially horizontalposition to which they are turned. This relatively sharp bending of thesheets in their path of travel tends to separate most sheets whichadhere together. As the top of the sheet which is engaged by the suctioncup is bent in on the path described, the top of the second sheet whichmay be adhering tends to travel straight up. Separation usually occursand the second sheet drops back to its normal position in the basket. Ithappens, however, that this sharp bending is not sufficient to effectthe separation of the sheets.

Extending above the sides of the tank are supporting plates l3 in whichare carried a pair of horizontally extending receiving rolls [4 and asimilar pair of feeding rolls Hi. The rolls M are arranged to receivethe leading edges of the sheets as they are progressively brought up tothe bite of the rolls by the suction cup mechanism previously described.The rolls I5 are adapted to receive the sheets after they have passedthrough the rolls M and. direct them into the pot of the dippingmachine.

The lower of the two rolls M is provided with an annular groove Hi. AtI1 is a finger having a forwardly inclined portion which extends intothe groove Hi, the arrangement being such that as a sheet passes throughthe rolls i l the front edge of the strip will travel over the fingeri1, being held at a predetermined elevation thereby. Extending acrossthe top of the machine frame above the rolls M is a supporting bar 13.Extending across the top of the bar i8 is a plate l9. This plate isprovided along one edge with upstanding ears 29. On the bar [8 are otherears 2|. A rod 22 passing through the ears and 2| provides a pivoted orhinged support for the plate [9. The plate l9 has two downwardly turnedextensions 23 having ears 24 thereon. The ears 24 support a rod 25 onwhich is carried a presser foot 26. The rod 25 provides a pivotedsupport for the presser foot 29. The outer end of the presser foot has aV-shaped notch 26a formed therein. Secured to the presser foot 26 is apost 2'! having a laterally extending arm 28 thereon. This arm isprovided with an adjustable counterweight 29. Secured to the plate [9 isa horizontally extending bar 39 having a transverse pin 3! thereinadapted to form a stop against which the post 2'! will move when thepresser foot moves to the dotted line position shown in Figure 2.

Cooperating with the presser foot 26 is a deflector 32, the deflectorhaving a point 32a which, as shown in Figure 4, extends down into thenotch 26a of the presser foot 26. Back of the point or nose 32a is anupwardly curved guide plate 3%. This terminates adjacent a pair of rolls33. On the delivery side of the rolls 33 there is a guide 34. Extendingover top of the mechanism is a receiving plate 35.

In the operation of the machine, the presser foot is normally in theposition shown in Figure 1 where the bottom of the plate 26 issubstantially flush with the bottom of the deflector 32. The presserplate or foot 26 is prevented from dropping below this point by reasonof the pin 3| forming a limit stop. When a sheet passes through therolls Hi, the leading edge rides up the top surface of the finger I! andstrikes the presser foot 26. The counterweight 29 is so set that when asingle sheet strikes the presser foot, the presser foot will deflect theedge of the sheet below the nose 32a and the edge of the sheet willtravel through to the rolls 15. When, however, a double passes throughthe rolls I4 and the edges travel up the finger H, the edge of thedouble is not so flexible as the edge of the single sheet, and thepresser foot is swung backwardly to the position shown in Figure 2.Ordinarily the double or the two sheets adhering together will then becaught by the nose 32a of the deflector, carried up the guide 32b,caught by the rolls 33, pushed against the guide 34 and thrown over ontothe receiving platform 35. Occasionally the doubles will be split orseparated by the nose 32a, as shown in Figure 2, in which case the lowersheet will continue onto the feeding rolls l5, while only the uppersheet will be caught by the nose 32a and thrown out of the line of feed.

It will be seen that the presser foot guides the sheets under thedeflector 32 or over it according to the resilience of the sheets. Asingle sheet will not raise the presser foot, whereas the edges of thedouble being less resilient because of the double thickness of themetal, will lift the presser foot. The counterweight 29 provides theonly adjustment which is necessary. By moving the counterweight 29 tothe left as viewed in Figure 1, the presser foot will resist a greaterpressure, and by moving the counterweight 29 toward the right thepresser foot can be made to lift under a less pressure. counterweight 29for the run of sheets for which the machine is designed to operate andthereafter no further adjustment is required. The pivoting of the plate19 .on the shaft 22 enables the whole mechanism carried on the plate [9to be lifted upwardly in the event of any jam occurring.

The rolls I4, l5 and 33 may be all connected together to operatecontinuously and simultaneously, such arrangements being commonlyprovided for all sheet feeders for tin plate machines. The drivingarrangements are more fully disclosed in our said copending application.

While we have illustrated and described a specific embodiment of ourinvention, it will be understood that various changes and modificationsare contemplated therein.

We claim:

A double throwout mechanism for sheet feeding devices comprising a pairof feed rolls one of which has an annular groove in the peripherythereof, a supporting finger at the discharge side of the feed rollsprojecting into the groove and designed to support the edge of the sheetafter it emerges from the rolls and hold it at a predetermined level, apresser foot arranged above said finger and arranged to engage the edgeof a sheet coming from said rolls and exert a downward pressure thereon,and a deflector following the presser foot for separating the singlesheets which yield to a greater extent than the double sheets whichyield to a lesser extent under the influence of the presser foot.

WILLIAM JONES. ALEXANDER R. WEIBEL.

It is merely necessary to adjust the 1

